As bakery operations have become automated over the years, machines have been developed to rapidly and accurately slice rolls such as hamburger buns. One machine of this type is shown in the present inventor's U.S. Pat. No. 4,048,883, and uses a moving endless band as a knife to slice the rolls. The rolls move toward the knife on a moving conveyor, and then a pressure applying arrangement applies pressure to the top surfaces of the rolls in order to ensure that the top and bottom surfaces are positioned so that the knife will pass substantially intermediate the top and bottom surfaces, and in order to ensure that the roll does not tilt or move sideways as it is being sliced. While the pressure applying arrangement disclosed in this patent has been adequate for its intended purposes, it has not been satisfactory in all respects.
Another existing device has several moving endless belts with lower reaches which can engage the tops of the rolls, each lower reach being urged downwardly by two spring-based rollers which engage the middle of the lower reach at locations spaced in the direction of movement of the lower reach. While adequate for its intended purposes, this known device has not been entirely satisfactory. Although it works in slicing machines which use rotating disks for slicing, it has not worked well with band-type slicing machines, in part because the rolls have a tendency to shift sideways.
Accordingly, one object of the present invention is to provide an improved pressure applying device for use in a roll slicing machine, which is more reliable than known arrangements in positioning and preventing sideways movement of the rolls.